SD28 waterproof plug connectors is  a large sized plastic shell IP68 waterproof wire connector.The user can attach the wires to the connector by solering & screw.

SP21 connector is  a large sized plastic shell IP68 waterproof wire connector.The user can attach the wires to the connector by solering & screw.

12 pin M20 connector is screw type IP67 waterproof electrical connector.

The user can attach the wires to the connector by screw.

Inheriting the same design to the A-Type connector used in USB 2.0 application, but USB 3.0 Type A processes additional pins that are not in the USB 2.0 A Type. USB 3.0 connectors are often in blue color to help distinguish them from previous generations.